1. Field of the Invention
The present invention relates to a system for aiding the preparation of an operation and maintenance plan for a power generation installation, and, in particular, relates to an operation and maintenance plan preparation aiding system for a power generation installation, in which a service center is provided. The service center manages operation and maintenance of a plurality of power generation units and prepares an operation and maintenance plan for respective power generation units by making use of plant data obtained from the respective power generation units through a communication network.
2. Conventional Art
Generally, many electric power generation companies, which operate an electric power generation business, own a plurality of power generation units. In order to manage the amount of power generated by these power generation units as a whole, comprise respective power generation systems are provided with a power supply command center (central supply) for every electric power generation company. In such power generation systems, the power supply command center assigns and adjusts the power generation amount for every power generation unit in response to power demand from consumers and each of the power generation units performs an operation while maintaining and adjusting the power generation amount assigned by the power supply command center. In such instances, the power supply command center prepares, in view of enhancing economy, an operation plan for the concerned power generation system so as to minimize fuel cost used in the power generation units, and to maximize power generation efficiency. As well, the command center prepares a plan, in view of placing priority on environmental protection, to keep the exhaust gas amount, such as nitrogen oxides and carbon dioxides exhausted from the power generation units, within an allowable range.
Now, the characteristics with regard to power efficiency and the exhaust gas amount which are used as references for the operation planning vary greatly depending on the kinds of fuel used and the power generation methods. With regard to fuels, in case of a thermal power generation, many kinds of fuels such as coal, petroleum and natural gas can be used, therefore, depending on the kind of fuels used, not only the power generation amount per unit fuel cost but also the amount and contents of the exhaust gas vary greatly. Further, with regard to power generation methods, the constitutions of machines and apparatuses of themselves such as power generation by a steam turbine, power generation by a gas turbine and a combined power generation combining thereof affect greatly their power generation efficiency. The power supply command center stores and preserves plant data (data representing the plant characteristics) obtained from these power generation units for every power generation unit, and uses the plant data when preparing operation plans for respective power generation units.
In the above referred to conventional power generation system, although the power supply command center stores and preserves the plant data for every power generation unit, these plant data were limited to the plant data at comparatively early stage of the respective power generation units, such as design values and those at the operation starting period of the power generation plants, however, the plant data varies gradually depending on passage of time as well as the contents of fuel being used, which also varies, therefore, it is difficult to prepare operation plans based on the current plant characteristics of the respective power generation units by making use only of the plant data.
Further, the above referred to conventional power generation system, since the machines and apparatuses such as a gas turbine constituting the power generating unit are always exposed to a high temperature, if load variation to the machines and apparatuses is frequently and repeatedly caused, deterioration of the machines and apparatuses due to thermal fatigue rapidly advances. For this reason, even if a fully economic operation which simply minimizes fuel cost for respective power generation units is employed, when the load variation to the machines and apparatuses is repeated, the lifetime of the machines and apparatuses is shortened, thus quickening the exchange time thereof, and therefore the total cost for the respective power generation units necessary for the plant operation, including the maintenance cost, is not necessarily minimized. Further, in the above referred to conventional power generation system, even if a plurality of power generation units having a high power generation efficiency are positively selected for the operation, when a provability of failure of the machines and apparatuses and the parts thereof constituting the power generation unit concerned is high, an unplanned outage is caused by a failure occurrence in the machines and apparatuses and the parts thereof which possibly causes an economic loss, therefore, even when an operation plan for a plurality of power generation units is prepared only based on fuel cost, the resultant cost was not necessarily minimized.
The present invention has been achieved in view of the above technical background, and an object of the present invention is to provide a system for aiding in the preparation of an operation and maintenance plan for a power generation installation in which an operation plan for a plurality of power generation units is prepared by making use of actual plant data, and being based on a total judgement, including a variety of circumstances of the machines and apparatuses and the parts thereof in the power generation units.
A first aspect of the present invention is to provide a system for aiding in the preparation of an operation and maintenance plan for a power generation installation in which a plurality of power generation units, a power supply command center and a service center are arranged and connected via communication networks, the service center obtaining plant data from the plurality of power generation units via the respective communication networks. For every power generation unit, the service center calculates power generation efficiency for the concerned power generation units in real time by making use of the obtained plant data and design data of the concerned power generation units and prepares operation and maintenance plans for the respective power generation units based on the calculated power generation efficiency.
According to the first aspect of the present invention, since the operation and maintenance plans for the respective power generation units are prepared in the service center based on the power generation efficiency evaluated and calculated in real time, a secular change and a performance degradation due to failure occurrence for the respective power generation units can be taken into account, thereby, the operation cost thereof can be reduced in comparison with the conventional power generation system in which the operation and maintenance plans for the respective power generation units are prepared by making use of the plant data.
A second aspect of the present invention is to provide a system for aiding in the preparation of an operation and maintenance plan for a power generation installation in which a plurality of power generation units, a power supply command center and a service center are arranged and connected via communication networks, the service center obtains plant data from the plurality of power generation units via the respective communication networks, and for every power generation unit, estimates process values in a machine and apparatus model by making use of the obtained plant data, determines deviation values between the estimated values and measured values, calculates from the determined deviation value a cost of economical loss caused by a power generation efficiency reduction of the concerned power generation unit, and prepares operation and maintenance plans for the respective power generation units through comparison between the calculated cost of economical loss and a cost relating to exchange of the machine and apparatus and the parts thereof in the concerned power generation unit.
According to the second aspect of the present invention, when preparing the operation and maintenance plans for the respective power generation units in the service center based on the power generation efficiency evaluated and calculated in real time, since the cost of economical loss due to the performance degradation is calculated from the deviation value between the process value estimated with the machine and apparatus model and the measured value, the cost of economical loss is compared with the cost relating to the exchange of the machine and apparatus and the parts thereof and the operation and maintenance plan of the respective power generation units are prepared by making use of the comparison result, the total cost for the operation and maintenance can be reduced.
A third aspect of the present invention is to provide a system for aiding in the preparation of an operation and maintenance plan for a power generation installation in which a plurality of power generation units, a power supply command center and a service center are arranged and connected via communication networks. The service center obtains plant data from the plurality of power generation units via the respective communication networks. For every power generation unit, the service center calculates remaining lifetime of the machine and apparatus and the parts thereof in the concerned power generation unit by making use of the obtained plant data and prepares operation and maintenance plans for the respective power generation units by determining exchange time of the machine and apparatus and the parts thereof in the concerned power generation unit based on the calculated remaining lifetime thereof.
According to the third aspect of the present invention, when preparing the operation and maintenance plans for the respective power generation units in the service center based on the power generation efficiency evaluated and calculated in real time, since the operation and maintenance planes are prepared based on the calculated remaining lifetime, an exchange timing of the machine and apparatus and the parts thereof can be determined with high accuracy in comparison with the conventional power generation system in which exchange of the machine and apparatus and the parts thereof is performed with reference to an accumulated operation time thereof, as a result, an abnormality occurrence due to use of the machine and apparatus and the parts thereof exceeding their lifetime and generation of economical loss due to unplanned outages caused by an abnormality of the machine and apparatus and the parts thereof can be prevented, moreover, an exchange at every predetermined period of the machine and apparatus even if there is a remaining lifetime is unnecessitated, thereby, the maintenance cost can be reduced.
A fourth aspect of the present invention is to provide a system for aiding in the preparation of an operation and maintenance plan for a power generation installation in which a plurality of power generation units, a power supply command center and a service center are arranged and connected via communication networks, the service center obtaining plant data from the plurality of power generation units via the respective communication networks and, for every power generation unit, calculating remaining lifetime of the machine and apparatus and the parts thereof in the concerned power generation unit by making use of the obtained plant data, comparing the calculated remaining lifetime with remaining lifetime of the machine and apparatus in the power generation unit determined in the other power generation unit, modifying the operation condition for the machine and apparatus and the parts thereof so as to enhance economy and prolong or shorten the remaining lifetime of the machine and apparatus and the parts thereof in the concerned power generation unit, thereby, preparing the operation and maintenance plans for the respective power generation units.
According to the fourth aspect of the present invention, when preparing the operation and maintenance plans for the respective power generation units in the service center based on the power generation efficiency evaluated and calculated in real time, since the operation condition for the machine and apparatus in its own power generation unit is modified based on the remaining lifetime of the machine and apparatus and the parts thereof not only in its own power generation unit but also in another power generation unit, the operation and maintenance plans can be prepared so that the total cost necessary for the operation and maintenance for the respective power generation units is minimized, the cost merit obtained by the electric power generation by the electric power generation company can be increased in comparison with the conventional power generation system.